Focus drawing scale



' May '30, 1944.

H. SCHELLER Focus DRAWING SCALE Filed Aug. 1G, 1943 ll/l lll INV ENT OR. 7M/y 52% e //er BY HMWf 4,.

` observe better.

Patented May 30, 1944 FOCUS vDRAWING SCALE Henry Scheller, New York, NfY. i h Application August 16, 1943, `Serial No. 498,752 r (ci. .a5-zc) h -2 Claims.

This invention relates. to improvements in drawing devices and more specifically to a new` and improved focus drawing scale adapted to facilitate drawing in the perspective.

To learn khow to draw in the perspective, free f hand representation of objects as they appear to the eye,is an important factor in the education of the child. Drawing in the perspective is the best medium 'to improve the child's power of observation. When drawing, the intensestudy of the subject, the focusing of eachfline, the` measuring and comparing of. lines with each other, are the `best means to train the child to rather than the drawingl` of the unes, that tend to improve the childs power of observation.

l is on the upper side of disk 3, -adjacent to its circular edge, and the edgesof aperture! are provided with a graduation 3, as may be seen in Fig. 1. A ring 8, engaging the annular groove l, is adapted to be rotated relative to disk 3. Seg- I ments Il, which are secured to ring 9, carry a strip Il extending centrally over disk3 so that the half-way point ofstrip Il coincides in all positions with the center point of disk 3.

`Whereas the embodiment of the invention illustrated in Figs. 1 and 2 is designed to be manufactured primarily of cardboard` or the like, the' j modification shown in Figs.` 3 and 4 is designed It is the study of the subject j Themain objectof the present invention is,

therefore, the provision of a focus drawing scale which facilitates the correct study of subjects to `be drawn in 'the perspective, thus guiding thev y childs natural impulse to investigate into a logical endeavour. j

Another object of the present invention is the provision of a focus drawing scale which is furnished with a corrector so that the child can correct the work accomplished, rooting the childs belief in its own ability and strengthening his desire for further efforts and progress.

In the drawing.: l h Figure 1 is a top plan view of a preferred embodiment of the invention;

Fig. 2 is a sectional view on the ling 2-2 ot Fig. 1';

`to be made of plastic material, metal `or similar material. According to this modification, to the base plate l is secured by means of rivets l or the like, a disk 3 having an inwardly inclined circular edge l 2 which engages the inclined inner edge I4 of ring l, as may be seen in Fig. 4.

This member 3v is used instead of a guide made up of the two parts 2 and 3 of Fig. `l, thereby simplifying the structure. The center strips which divide the aperture 5 into four square shaped parts of equal size can be substituted by a cross-piece I3 which forms a unit Iwith disk 3. According to this modification, I prefer to make the strip Il as a unit with the ring 3 and to increase its width at both ends as shown in Fig. 3. so as to have space enough for perforations or windows Il, through which the dial `I4 can be seen. `The `windows l1 can be provided with pointed parts i3, whichfare in alignment with the middle axis of strips ll and which are adapt- Fig. 3 is a top plan view'ofl modification oi thefocus drawing scale;

Figures 5 to 17 inclusiveare diagrams illustrating the various uses of the device;these diagrams will be explained in `detail hereinafter.

Similar numerals `refer to .similar parts throughout the several views.

Referringfirst to Figs. 1 and 2, the numeral l designates" a. base line of cardboard orthe like to which a circularplate 2vofFig. 2 of the same or ofA a similar material is secured by` means of gluing or in any other suitablemanner. A disk 3, the diameter of which is larger than the diameter of the circular plate 2, is coaxially secured `to plate 2 in such a manner. that thedisk 3. and thelpla'tes l and 2 form an-annular groove I v(Fig.

2)."The disk 3 and the plates I and 2 are provided with centrallylocated square-shaped perforations which register lwith eachother, th-us forming a window or aperture 5, Center strips i, connecting the `centers of each two opposite sides of the square-shaped `aperture 5 to each other and crossing each other in the center point of disk 3, divide the aperture 5 into four square parts of equal size. A graduated angle meter dial i y Fig. 4 is a sectional view on the line 4 4 of Fig.3:

h from the eye.

ed to facilitate the angular adjustment ot ring 3 on the dial 1. The dial 1 ls preferably graduated from 0 to 90 and an additional graduation of O to 360 can be provided in the dial 1 as shown in Fig. 3.

The device is to be used ner:

Before drawing a scene or object, one frames that part of the subject which one wishes to illusin the following man- `trate,`by looking at the subject through aperture i. As indicated in the diagrams Figs. 5 and 6,-

in which the numeral 20 designates the eye, and the numeral 2| the size of the subject, one gets more of the subject in the apertureof the focus drawing scale by holding the device closer to the eye (Fig. `6), than if one `holds it further away (The device should always be heldin an exact upright, right angle position, and when focusing, only one eye should be used for sharp one-point vision.) When the subject hasr been focused satisfactorily, the lfour squares into which Athe aperture 5 is subdivided, will indicate the position of the different parts for spacing and placing them onthe drawing.

' An important feature of drawingin the perspective is the inding of the eye-line 22 (Fig. 7) This means the establishing of an imaginary line which runs across the scene to be drawn in the exact height of the eye. This line cuts the scene in two parts. an upper and a lower part.

Rays in the upper part have to come downwards to reachthe eye, while rays fromthe lower part have to come upwards to reach the eye. To get the exact eyeline of the subject. one places the focus drawing scale in front of the eye, in a right angular upright position, looks straight through aperture 5 so that the point at which the center strips 5 cross each other will be the same height as the eye. The points at which the strips 5 cross each other will then indicate exactly the eyeline or line of vision 22.

Before drawing a line, one focuses its direction using thereto the three vertical lines 23, 24 and and the three horizontal lines 2'|, v28 and 29 (Figs. 8 and 9), which are represented by the edges of aperture 5 and by the center strips 6. Looking through the aperture 5, one compares the line to be drawn with the nearest ofthe three horizontal or vertical lines represented by or in aperture 5.

Having focused a line and having established the correct direction, one has to .measure and compare the line with lines-already drawn or lines near toit.

When measuring lines, one should try to measure as many lines togetheras possible.

One moves the focus drawing scale back and forth until the largest line fills the full length of the aperture 5. The larger line then is a unit while the smaller lines will be the fraction thereof. This way it is possible to measure two lines or 'more at the same time. The edges of the aperture 5 have a graduated scale 8 which will give at a glance the fractions.

establish. For instance, if in Fig. 16 the line 45 is used as base line, one focuses lfirst the line 4| by bringing the strip il in the position shown in the upper circle of Fig. 17; then one focuses the line 42 (Fig. 16) by bringing the strip in the position shown in the lower circle of Fig. 17;

l the point 43 at which the line 4| crosses the When objects are very small, one uses one of the four squares instead of the whole aperture 5 for measuring and comparing. In Fig. 10, a door 30 is shown as it appears to the eye, and Fig. 11, the door is indicated in dash-and-dotted lines 32 and 33. There it can be seen that, in this :inv stance, the long line 3| registers with vtheentire vertical side 23 of aperture 5, whereas the lengthy of thesldes 32 and 33 of the door appear only as fractions of the edges of aperture 5. Y*

When measuring av circle, as for instance the opening of the cup 40 shown rin Fig. 12, one focuses'one of the center strips 6 of the aperture V.li across the center of the circle and .moves the focus drawing scale back and forth until the whole width of the circle fllsthe full lengthvof the aperture 5. 'I'hen one can compare the breadth of the circle with the depth. One also has two halves, one half nearer to the eye and the other farther away and their difference in size, as indicated in dash-and-dotted lines in Fig. 13.

If, after one has drawn a line and wants to make sure of its right position, one can use the degree indicator (strip Il) as a corrector tomake certain. For this purpose, thei'ocus 'drawing scale is to beheld so that one of the cross strips 6 (or one of the cross-pieces I6) is in a vertical and the other in a horizontal position ,and moves the strip i leven with the line one wants to correct. One brings the focus drawing scale down on the drawing also in a right angle position and compares with the line drawn. Then one can see whether the line is correct or how much it is out of the way. For instance, if Fig. 14 represents a line to be checked, the strip Il must be in the position shown in Fig. 15. v

line 42, indicates then the location of the point to be found,

If one does not have a line to use as va. base, one can use two established points to focus in one other point by focusing one line from each of the two established points tothe point one wants to nd and proceeds in the same manner.

Having thus described my invention, what I claim and desire to secure by Letters Patent in the United States is:

l. A focus drawing scale comprising a base plate having a square aperture in its center, a circular plate secured to said base plate andhaving an aperture in its center which registers with .the aperture in said base plate; a disk the diameter of which is larger than that of said circular plate, coaxially secured to said circular plate so as to form an annular groove with said base plate, and having an aperture registering with the aperture in said circular plate; center strips connecting the center of each two opposite sides of said square apertures to each other and crossing each other in the center point of said disk; a ring engaging the .annular groove formed by said base plate, said circular plate and said disk; and a strip secured to the face of said ring and `adapted -to bemoved angularly over said disk when said ring is rotated relative to said disk; said strip being secured to said ring .at diametricallyk opposite points so that its half-way point always coincides with the center point of said disk, and said disk being graduated at itskouter circular edge and at the edges of its square aperture.

2. `Ay focus drawing; scale comprising la base plate having a centrally situated aperture, a disk secured to said base plate and having an inwardly inclined circular edge and `an ,aperture registering withr the aperture .in said base plate, an angle meter dial provided on the upper side of said disk adjacent its circular edge, a graduation at the edges of the aperturefof said disk, a cross secured to the said aperture and adapted to divide said aperture into four equalsquares, aring having an inwardly inclined inner yedge adapted vadjacent said strips, through which said angle meter dial is visible.

l HENRY SCI-IELLER. 

